| /* |
| * arch/ppc/kernel/irq.c |
| * |
| * Derived from arch/i386/kernel/irq.c |
| * Copyright (C) 1992 Linus Torvalds |
| * Adapted from arch/i386 by Gary Thomas |
| * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) |
| * Updated and modified by Cort Dougan (cort@cs.nmt.edu) |
| * Copyright (C) 1996 Cort Dougan |
| * Adapted for Power Macintosh by Paul Mackerras |
| * Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au) |
| * Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk). |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or (at your option) any later version. |
| * |
| * This file contains the code used by various IRQ handling routines: |
| * asking for different IRQ's should be done through these routines |
| * instead of just grabbing them. Thus setups with different IRQ numbers |
| * shouldn't result in any weird surprises, and installing new handlers |
| * should be easier. |
| */ |
| |
| #include <linux/errno.h> |
| #include <linux/module.h> |
| #include <linux/threads.h> |
| #include <linux/kernel_stat.h> |
| #include <linux/signal.h> |
| #include <linux/sched.h> |
| #include <linux/ioport.h> |
| #include <linux/interrupt.h> |
| #include <linux/timex.h> |
| #include <linux/config.h> |
| #include <linux/init.h> |
| #include <linux/slab.h> |
| #include <linux/pci.h> |
| #include <linux/delay.h> |
| #include <linux/irq.h> |
| #include <linux/proc_fs.h> |
| #include <linux/random.h> |
| #include <linux/kallsyms.h> |
| #include <linux/profile.h> |
| #include <linux/bitops.h> |
| |
| #include <asm/uaccess.h> |
| #include <asm/system.h> |
| #include <asm/io.h> |
| #include <asm/pgtable.h> |
| #include <asm/irq.h> |
| #include <asm/cache.h> |
| #include <asm/prom.h> |
| #include <asm/ptrace.h> |
| #include <asm/iSeries/ItLpQueue.h> |
| #include <asm/machdep.h> |
| #include <asm/paca.h> |
| |
| #ifdef CONFIG_SMP |
| extern void iSeries_smp_message_recv( struct pt_regs * ); |
| #endif |
| |
| extern irq_desc_t irq_desc[NR_IRQS]; |
| EXPORT_SYMBOL(irq_desc); |
| |
| int distribute_irqs = 1; |
| int __irq_offset_value; |
| int ppc_spurious_interrupts; |
| unsigned long lpevent_count; |
| u64 ppc64_interrupt_controller; |
| |
| int show_interrupts(struct seq_file *p, void *v) |
| { |
| int i = *(loff_t *) v, j; |
| struct irqaction * action; |
| irq_desc_t *desc; |
| unsigned long flags; |
| |
| if (i == 0) { |
| seq_printf(p, " "); |
| for (j=0; j<NR_CPUS; j++) { |
| if (cpu_online(j)) |
| seq_printf(p, "CPU%d ",j); |
| } |
| seq_putc(p, '\n'); |
| } |
| |
| if (i < NR_IRQS) { |
| desc = get_irq_desc(i); |
| spin_lock_irqsave(&desc->lock, flags); |
| action = desc->action; |
| if (!action || !action->handler) |
| goto skip; |
| seq_printf(p, "%3d: ", i); |
| #ifdef CONFIG_SMP |
| for (j = 0; j < NR_CPUS; j++) { |
| if (cpu_online(j)) |
| seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]); |
| } |
| #else |
| seq_printf(p, "%10u ", kstat_irqs(i)); |
| #endif /* CONFIG_SMP */ |
| if (desc->handler) |
| seq_printf(p, " %s ", desc->handler->typename ); |
| else |
| seq_printf(p, " None "); |
| seq_printf(p, "%s", (desc->status & IRQ_LEVEL) ? "Level " : "Edge "); |
| seq_printf(p, " %s",action->name); |
| for (action=action->next; action; action = action->next) |
| seq_printf(p, ", %s", action->name); |
| seq_putc(p, '\n'); |
| skip: |
| spin_unlock_irqrestore(&desc->lock, flags); |
| } else if (i == NR_IRQS) |
| seq_printf(p, "BAD: %10u\n", ppc_spurious_interrupts); |
| return 0; |
| } |
| |
| #ifdef CONFIG_HOTPLUG_CPU |
| void fixup_irqs(cpumask_t map) |
| { |
| unsigned int irq; |
| static int warned; |
| |
| for_each_irq(irq) { |
| cpumask_t mask; |
| |
| if (irq_desc[irq].status & IRQ_PER_CPU) |
| continue; |
| |
| cpus_and(mask, irq_affinity[irq], map); |
| if (any_online_cpu(mask) == NR_CPUS) { |
| printk("Breaking affinity for irq %i\n", irq); |
| mask = map; |
| } |
| if (irq_desc[irq].handler->set_affinity) |
| irq_desc[irq].handler->set_affinity(irq, mask); |
| else if (irq_desc[irq].action && !(warned++)) |
| printk("Cannot set affinity for irq %i\n", irq); |
| } |
| |
| local_irq_enable(); |
| mdelay(1); |
| local_irq_disable(); |
| } |
| #endif |
| |
| extern int noirqdebug; |
| |
| /* |
| * Eventually, this should take an array of interrupts and an array size |
| * so it can dispatch multiple interrupts. |
| */ |
| void ppc_irq_dispatch_handler(struct pt_regs *regs, int irq) |
| { |
| int status; |
| struct irqaction *action; |
| int cpu = smp_processor_id(); |
| irq_desc_t *desc = get_irq_desc(irq); |
| irqreturn_t action_ret; |
| #ifdef CONFIG_IRQSTACKS |
| struct thread_info *curtp, *irqtp; |
| #endif |
| |
| kstat_cpu(cpu).irqs[irq]++; |
| |
| if (desc->status & IRQ_PER_CPU) { |
| /* no locking required for CPU-local interrupts: */ |
| ack_irq(irq); |
| action_ret = handle_IRQ_event(irq, regs, desc->action); |
| desc->handler->end(irq); |
| return; |
| } |
| |
| spin_lock(&desc->lock); |
| ack_irq(irq); |
| /* |
| REPLAY is when Linux resends an IRQ that was dropped earlier |
| WAITING is used by probe to mark irqs that are being tested |
| */ |
| status = desc->status & ~(IRQ_REPLAY | IRQ_WAITING); |
| status |= IRQ_PENDING; /* we _want_ to handle it */ |
| |
| /* |
| * If the IRQ is disabled for whatever reason, we cannot |
| * use the action we have. |
| */ |
| action = NULL; |
| if (likely(!(status & (IRQ_DISABLED | IRQ_INPROGRESS)))) { |
| action = desc->action; |
| if (!action || !action->handler) { |
| ppc_spurious_interrupts++; |
| printk(KERN_DEBUG "Unhandled interrupt %x, disabled\n", irq); |
| /* We can't call disable_irq here, it would deadlock */ |
| if (!desc->depth) |
| desc->depth = 1; |
| desc->status |= IRQ_DISABLED; |
| /* This is not a real spurrious interrupt, we |
| * have to eoi it, so we jump to out |
| */ |
| mask_irq(irq); |
| goto out; |
| } |
| status &= ~IRQ_PENDING; /* we commit to handling */ |
| status |= IRQ_INPROGRESS; /* we are handling it */ |
| } |
| desc->status = status; |
| |
| /* |
| * If there is no IRQ handler or it was disabled, exit early. |
| Since we set PENDING, if another processor is handling |
| a different instance of this same irq, the other processor |
| will take care of it. |
| */ |
| if (unlikely(!action)) |
| goto out; |
| |
| /* |
| * Edge triggered interrupts need to remember |
| * pending events. |
| * This applies to any hw interrupts that allow a second |
| * instance of the same irq to arrive while we are in do_IRQ |
| * or in the handler. But the code here only handles the _second_ |
| * instance of the irq, not the third or fourth. So it is mostly |
| * useful for irq hardware that does not mask cleanly in an |
| * SMP environment. |
| */ |
| for (;;) { |
| spin_unlock(&desc->lock); |
| |
| #ifdef CONFIG_IRQSTACKS |
| /* Switch to the irq stack to handle this */ |
| curtp = current_thread_info(); |
| irqtp = hardirq_ctx[smp_processor_id()]; |
| if (curtp != irqtp) { |
| irqtp->task = curtp->task; |
| irqtp->flags = 0; |
| action_ret = call_handle_IRQ_event(irq, regs, action, irqtp); |
| irqtp->task = NULL; |
| if (irqtp->flags) |
| set_bits(irqtp->flags, &curtp->flags); |
| } else |
| #endif |
| action_ret = handle_IRQ_event(irq, regs, action); |
| |
| spin_lock(&desc->lock); |
| if (!noirqdebug) |
| note_interrupt(irq, desc, action_ret); |
| if (likely(!(desc->status & IRQ_PENDING))) |
| break; |
| desc->status &= ~IRQ_PENDING; |
| } |
| out: |
| desc->status &= ~IRQ_INPROGRESS; |
| /* |
| * The ->end() handler has to deal with interrupts which got |
| * disabled while the handler was running. |
| */ |
| if (desc->handler) { |
| if (desc->handler->end) |
| desc->handler->end(irq); |
| else if (desc->handler->enable) |
| desc->handler->enable(irq); |
| } |
| spin_unlock(&desc->lock); |
| } |
| |
| #ifdef CONFIG_PPC_ISERIES |
| void do_IRQ(struct pt_regs *regs) |
| { |
| struct paca_struct *lpaca; |
| struct ItLpQueue *lpq; |
| |
| irq_enter(); |
| |
| #ifdef CONFIG_DEBUG_STACKOVERFLOW |
| /* Debugging check for stack overflow: is there less than 2KB free? */ |
| { |
| long sp; |
| |
| sp = __get_SP() & (THREAD_SIZE-1); |
| |
| if (unlikely(sp < (sizeof(struct thread_info) + 2048))) { |
| printk("do_IRQ: stack overflow: %ld\n", |
| sp - sizeof(struct thread_info)); |
| dump_stack(); |
| } |
| } |
| #endif |
| |
| lpaca = get_paca(); |
| #ifdef CONFIG_SMP |
| if (lpaca->lppaca.int_dword.fields.ipi_cnt) { |
| lpaca->lppaca.int_dword.fields.ipi_cnt = 0; |
| iSeries_smp_message_recv(regs); |
| } |
| #endif /* CONFIG_SMP */ |
| lpq = lpaca->lpqueue_ptr; |
| if (lpq && ItLpQueue_isLpIntPending(lpq)) |
| lpevent_count += ItLpQueue_process(lpq, regs); |
| |
| irq_exit(); |
| |
| if (lpaca->lppaca.int_dword.fields.decr_int) { |
| lpaca->lppaca.int_dword.fields.decr_int = 0; |
| /* Signal a fake decrementer interrupt */ |
| timer_interrupt(regs); |
| } |
| } |
| |
| #else /* CONFIG_PPC_ISERIES */ |
| |
| void do_IRQ(struct pt_regs *regs) |
| { |
| int irq; |
| |
| irq_enter(); |
| |
| #ifdef CONFIG_DEBUG_STACKOVERFLOW |
| /* Debugging check for stack overflow: is there less than 2KB free? */ |
| { |
| long sp; |
| |
| sp = __get_SP() & (THREAD_SIZE-1); |
| |
| if (unlikely(sp < (sizeof(struct thread_info) + 2048))) { |
| printk("do_IRQ: stack overflow: %ld\n", |
| sp - sizeof(struct thread_info)); |
| dump_stack(); |
| } |
| } |
| #endif |
| |
| irq = ppc_md.get_irq(regs); |
| |
| if (irq >= 0) |
| ppc_irq_dispatch_handler(regs, irq); |
| else |
| /* That's not SMP safe ... but who cares ? */ |
| ppc_spurious_interrupts++; |
| |
| irq_exit(); |
| } |
| #endif /* CONFIG_PPC_ISERIES */ |
| |
| void __init init_IRQ(void) |
| { |
| static int once = 0; |
| |
| if (once) |
| return; |
| |
| once++; |
| |
| ppc_md.init_IRQ(); |
| irq_ctx_init(); |
| } |
| |
| #ifndef CONFIG_PPC_ISERIES |
| /* |
| * Virtual IRQ mapping code, used on systems with XICS interrupt controllers. |
| */ |
| |
| #define UNDEFINED_IRQ 0xffffffff |
| unsigned int virt_irq_to_real_map[NR_IRQS]; |
| |
| /* |
| * Don't use virtual irqs 0, 1, 2 for devices. |
| * The pcnet32 driver considers interrupt numbers < 2 to be invalid, |
| * and 2 is the XICS IPI interrupt. |
| * We limit virtual irqs to 17 less than NR_IRQS so that when we |
| * offset them by 16 (to reserve the first 16 for ISA interrupts) |
| * we don't end up with an interrupt number >= NR_IRQS. |
| */ |
| #define MIN_VIRT_IRQ 3 |
| #define MAX_VIRT_IRQ (NR_IRQS - NUM_ISA_INTERRUPTS - 1) |
| #define NR_VIRT_IRQS (MAX_VIRT_IRQ - MIN_VIRT_IRQ + 1) |
| |
| void |
| virt_irq_init(void) |
| { |
| int i; |
| for (i = 0; i < NR_IRQS; i++) |
| virt_irq_to_real_map[i] = UNDEFINED_IRQ; |
| } |
| |
| /* Create a mapping for a real_irq if it doesn't already exist. |
| * Return the virtual irq as a convenience. |
| */ |
| int virt_irq_create_mapping(unsigned int real_irq) |
| { |
| unsigned int virq, first_virq; |
| static int warned; |
| |
| if (ppc64_interrupt_controller == IC_OPEN_PIC) |
| return real_irq; /* no mapping for openpic (for now) */ |
| |
| if (ppc64_interrupt_controller == IC_BPA_IIC) |
| return real_irq; /* no mapping for iic either */ |
| |
| /* don't map interrupts < MIN_VIRT_IRQ */ |
| if (real_irq < MIN_VIRT_IRQ) { |
| virt_irq_to_real_map[real_irq] = real_irq; |
| return real_irq; |
| } |
| |
| /* map to a number between MIN_VIRT_IRQ and MAX_VIRT_IRQ */ |
| virq = real_irq; |
| if (virq > MAX_VIRT_IRQ) |
| virq = (virq % NR_VIRT_IRQS) + MIN_VIRT_IRQ; |
| |
| /* search for this number or a free slot */ |
| first_virq = virq; |
| while (virt_irq_to_real_map[virq] != UNDEFINED_IRQ) { |
| if (virt_irq_to_real_map[virq] == real_irq) |
| return virq; |
| if (++virq > MAX_VIRT_IRQ) |
| virq = MIN_VIRT_IRQ; |
| if (virq == first_virq) |
| goto nospace; /* oops, no free slots */ |
| } |
| |
| virt_irq_to_real_map[virq] = real_irq; |
| return virq; |
| |
| nospace: |
| if (!warned) { |
| printk(KERN_CRIT "Interrupt table is full\n"); |
| printk(KERN_CRIT "Increase NR_IRQS (currently %d) " |
| "in your kernel sources and rebuild.\n", NR_IRQS); |
| warned = 1; |
| } |
| return NO_IRQ; |
| } |
| |
| /* |
| * In most cases will get a hit on the very first slot checked in the |
| * virt_irq_to_real_map. Only when there are a large number of |
| * IRQs will this be expensive. |
| */ |
| unsigned int real_irq_to_virt_slowpath(unsigned int real_irq) |
| { |
| unsigned int virq; |
| unsigned int first_virq; |
| |
| virq = real_irq; |
| |
| if (virq > MAX_VIRT_IRQ) |
| virq = (virq % NR_VIRT_IRQS) + MIN_VIRT_IRQ; |
| |
| first_virq = virq; |
| |
| do { |
| if (virt_irq_to_real_map[virq] == real_irq) |
| return virq; |
| |
| virq++; |
| |
| if (virq >= MAX_VIRT_IRQ) |
| virq = 0; |
| |
| } while (first_virq != virq); |
| |
| return NO_IRQ; |
| |
| } |
| |
| #endif /* CONFIG_PPC_ISERIES */ |
| |
| #ifdef CONFIG_IRQSTACKS |
| struct thread_info *softirq_ctx[NR_CPUS]; |
| struct thread_info *hardirq_ctx[NR_CPUS]; |
| |
| void irq_ctx_init(void) |
| { |
| struct thread_info *tp; |
| int i; |
| |
| for_each_cpu(i) { |
| memset((void *)softirq_ctx[i], 0, THREAD_SIZE); |
| tp = softirq_ctx[i]; |
| tp->cpu = i; |
| tp->preempt_count = SOFTIRQ_OFFSET; |
| |
| memset((void *)hardirq_ctx[i], 0, THREAD_SIZE); |
| tp = hardirq_ctx[i]; |
| tp->cpu = i; |
| tp->preempt_count = HARDIRQ_OFFSET; |
| } |
| } |
| |
| void do_softirq(void) |
| { |
| unsigned long flags; |
| struct thread_info *curtp, *irqtp; |
| |
| if (in_interrupt()) |
| return; |
| |
| local_irq_save(flags); |
| |
| if (local_softirq_pending()) { |
| curtp = current_thread_info(); |
| irqtp = softirq_ctx[smp_processor_id()]; |
| irqtp->task = curtp->task; |
| call_do_softirq(irqtp); |
| irqtp->task = NULL; |
| } |
| |
| local_irq_restore(flags); |
| } |
| EXPORT_SYMBOL(do_softirq); |
| |
| #endif /* CONFIG_IRQSTACKS */ |
| |
| static int __init setup_noirqdistrib(char *str) |
| { |
| distribute_irqs = 0; |
| return 1; |
| } |
| |
| __setup("noirqdistrib", setup_noirqdistrib); |